Comment 38 for bug 1006446

I see the exact same thing as perpetualrabbit: client(s) experience nfs lockup for several tens of seconds - of the server side ~5 nfs threads killing the cpu.

This began on upgrading a client from 10.04 LTS to 12.04 LTS. The server is Debian Squeeze with 3.2.0 backport kernel. The server has no issues with Fedora 17 or previous versions of Ubuntu, each having their /home dir on the server over NFS4.

It seems the problem arises with files of largish size. I first noticed this watching a 10-minute Youtube-video, which I assumed creates a temporary file somewhere under /home/$ME - the hang does not happen on "private browsing".

This is to note, that I think this problem is specifically related to Ubuntu. I had no such problems when Fedora was at kernel 3.2